Microsoft reveals Windows Phone 8.1

The days of Microsoft playing third fiddle to Apple and Google in the smartphone OS stakes may soon be over, after the software giant unveiled its new Windows Phone 8.1 OS.

The update brings a multitude of new features to the mobile platform, including the Cortana digital assistant - Windows Phone's answer to Siri - the notifications-friendly Action Centre and a Swype-style keyboard.

Other additions to the OS include a redesigned lock screen, the option to display your wallpaper behind Live Tiles and business-friendly features such as VPN support and the ability to read encrypted emails.

The mobile OS wasn't the only new software Microsoft revealed at its Build developer conference in San Francisco - the Windows 8.1 Update for PCs was also announced, and will be available for free next week.

Say Halo to Cortana

If the name Cortana sounds familiar, you're obviously a fan of classic Xbox FPS Halo - in the game, she was an advanced AI which acted as faithful personal assistant to the lead character Master Chief. Microsoft clearly intends for the WinPho8.1 version to fulfil much the same role, though presumably without helping you get all kill-happy.

The service will be heavily linked to Microsoft's Bing search engine and will be fully voice-controllable. You'll be able to use it for standard tasks such as setting calendar entries, but more impressively, it will learn about your habits, tastes and contacts, and understand natural language. Introducing the service, Microsoft's Joe Belfiore gave the example of telling Cortana to "remind me to ask my sister about her puppy next time I speak to her"; Cortana worked out instantly who his sister was and set a reminder that would flash up next time he called her.

Chief to this working properly will be the Notebook feature in which Cortana will store information about your interests, the people who matter to you and what your daily habits are. As she learns more about you, Cortana will add entries to the Notebook, which you'll be able to approve or otherwise. If she comes to the conclusion that your wife is someone important to you, for instance, she'll add her to your 'Inner circle'. If you don't correct that information, she might make the decision to put a call from your wife through to you even if it comes in during your designated 'quiet hours'.

So in short, Cortana will meld Siri-like talents with Google Now-style capabilities, but judging by the demonstration given by Belfiore, she looks twice as clever as the pair of them put together. We're interested to see how smart she is in the real world.

Online Editor, Asia

No Cortana for Asia Pacific... for now

Don't expect to say hi to Cortana anytime soon. According to HardwareZone, the digital personal assistant won't be available when Windows Phone 8.1 is rolled out. The consolation, is that it will eventually be available. You'll just have to hang in there till 2015.

Other new talents

If Cortana is the big new feature arriving in Windows Phone 8.1, there are several others that you're likely to use far more regularly.

Action Center is a notifications hub; pull it down from the top of the screen and you'll have access to settings such as Wi-Fi and Bluetooth as well as seeing a list of recent texts, emails and app updates. Yes, it's a feature that's been available in iOS and on Android for a while, but better late than never.

The new lock screen, meanwhile, can also display notifications and calendar entries, while there's also now the ability to set the background behind the Live Tiles on your home screen.

Finally, the Work Flow keyboard now supports swipe-based text input - and impressively so. Belfiore used the new input method onstage, and also revealed that it recently claimed a world record previously held by the Samsung Galaxy S4. Yes, there's a world record for speed-typing-on-a-phone.

The OS will roll out on to existing devices "over the next few months", but may arrive before then on new handsets such as the Nokia Lumia 930 and Lumia 635 this May/June. We'll review it in full just as soon as we can.